Continuous impregnation plant of cardboard or like support

ABSTRACT

Installation for the continuous impregnation of cardboard, felt, or other similar products, in corrugated or noncorrugated sheets comprising a tank of generally parallelepipedic shape, the two end walls of which are inclined so as to permit progressive ingress and egress of sheets or boards of card, felt, or other similar material in continuous succession into and out of the impregnation product, which is liquid or brought to and kept in the liquid state and which is introduced into said tank, said sheets or boards being held vertical between two pairs of conveyor chains, namely a bottom pair and a top pair, which carry them from an end for the entry and introduction of the sheets or boards between the chains to the other end, which is the outlet and where the sheets are unhooked after having been entirely immersed over a large part of their travel in the impregnation bath.

United States Patent [72] inventor Roger Vallon Rouen, France [21 1 Appl. No. 834,069 [22] Filed June 17, 1969 [45] Patented Aug. 24, 1971 [73] Assignee Societe Anonyme: 0.F.l.C. Omnium Francais Industrial Et Commercial Paris, Fram [32} Priority July 16, 1968 [33] France [31} 159386 [54] CONTINUOUS IMPREGNATION PLANT 0F CARDBOARD 0R LIKE SUPPORT 6 Claims, 5 Drawing Figs. [52] US. Cl 118/423, 198/165 [51] Int. Cl B05c 3/00 [50] Field of Search 118/423; 198/165, 46, 47 [56] References Cited UNITED STATES PATENTS 545,429 8/1895 Lewis 118/423 2,235,824 3/1941 Cary 3,312,326 4/1967 Huppenthal Fri/nary Examiner-Mervin Stein ABSTRACT: Installation for the continuous impregnation of cardboard, felt, or other similar products, in corrugated or noncorrugated sheets comprising a tank of generally parallelepipedic shape, the two end walls of which are inclined so as to permit progressive ingress and egress of sheets or boards of card, felt, or other similar material in continuous succession into and out of the impregnation product, which is liquid or brought to and kept in the liquid state and which is introduced into said tank, said sheets or boards being held vertical between two pairs of conveyor chains, namely a bottom pair and atop pair, which carry them from an end for the entry and introduction of the sheets or boards between the chains to the other end, which is the outlet and where the sheets are unhooked after having been entirely immersed over a large part of their travel in the impregnation bath.

23 41 17 1 25 1 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 l 1 1 24 oi 1 1 1 '1 1 1 I 1 1 p is n 15 23 39 13' 12 13 39 1 1 1 1 l E 30 g 9 1 1 1 1 1 n 1 r 1111 y 11 1111 11111 111 11111 g 1 1 1 5 Patented Aug. 24, 1971 2 Sheets-Sheet 1 MN R Q &

INVENTOR ROGER VALLON MELVILLE, STRASSER, FOSTER and HOFFMAN ATTORNEYS CONTINUOUS IMPREGNATION PLANT OF CARDBOARD OR LIKE SUPPORT materials, which consists in immersing in a bath of hot bitumen, for example, the sheets which are held in cages suspended above the bath by means of a pulley block. This method makes it possible to obtain complete impregnation of the material, but only in a discontinuous manner.

Another known process consists in projecting hot bitumen on to the two faces of a continuous sheet circulating between banks of projectors situated on each side of the sheet. This process, which permits continuous movement of the material, nevertheless does not effect its complete impregnation.

The present invention has as object an installation making it possible to achieve complete and also continuous impregnation of sheets or boards of card or other material so as to form a dry, nonsticky product.

The installation forming the object of the invention comprises a tank of generally parallelepipedic shape, the two end walls of which are inclined so as to permit progressive ingress and egress of sheets or boards of card, felt, or other similar material in continuous succession into and out of the impregnation product, which is liquid or brought to and kept in the liquid state and which is introduced into said tank, said sheets or boards being held vertical between two pairs of conveyor chains, namely a bottom pair and a top pair, which carry them from an end for the entry and introduction of the sheets or boards between the chains to the other end, which is the outlet end where the sheets are unhooked after having been entirely immersed over a large part of their travel in the impregnation bath.

The top and bottom chains, which are parallel to one another, are connected in each pair by spacers, on which there are clipped springs holding the sheets in a vertical position and at regular intervals in the bath.

The bath is heated by coils through which hot fluid such as oil or steam may circulate, situated at the bottom and on the inside walls of the tank.

A reservoir and pumping unit makes it possible for the impregnating material to be recycled together with makeup material.

The chains move at a speed which may vary in accordance with the thickness of the product to be impregnated and the density of the impregnating material.

The slides on which the chains run may be completely or partly heated outside the bath in order to prevent material from sticking to the chains, which would have the effect of considerably increasing the driving torque.

A form of construction of the installation is described below, simply by way of example without limitation, and with reference to the accompanying drawings, in which:

FIG. 1 illustrates diagrammatically the whole installation,

FIG. 2 is a plan view of a fragment of the bottom conveyor system,

FIG. 3 shows the shape of the support springs,

FIG. 4 shows the shape of the side stop springs,

FIG. 5 is a view in elevation of a sheet placed in position between the top and bottom conveyor systems.

The installation comprises a tank 1 of generally parallelepipedie shape, with raised end walls and a flat bottom, the depth of which is substantially greater than the height of the sheets or boards to be impregnated.

The tank 1 is of metal or other material considered suitable, and is thermally insulated to prevent the loss of heat.

In the tank 1 there are sides 2, 3, and 4 in the form of a vat extending along the bottom and inclined end walls, which slides are supported by the longitudinal walls while two parallel conveyor chains 5 can run over them. Corresponding slides 2 6, 7, and 8 are installed beneath the tank and beneath the inclined walls in order to guide the bottom runs of the conveyor chains 5.

The chains 5 are likewise guided by pinions 9 rotating freely on fixed shafts mounted on plain bearings carried by the metal frame of the installation. They are driven by two driving pinions 10 keyed on a shaft 11 receiving its rotational movement from any suitable driving means.

Parallel to the two bottom conveyor chains 5 there are installed, exactly above them, two top conveyor chains 12 running on the one hand on horizontal slides 13 and inclined slides 14 and 15 situated partly in the tank 1, and on the other hand on horizontal slides 16 situated at the top of the installation.

The upper chains 12 are guided by pinions 17 similar to the pinions 9 and mounted in the same manner as the latter with regard to that part of them situated at the highest level. With regard to the parts situated directly above and in the tank, their bottom side can run on horizontal slides 13 enabling the chains to carry sheets or boards of greater height.

Consequently, the bottom side of the chains 12 passes over pinions 18, 19, 20, 21, 22 mounted on sliding chairs which can be brought to the desired level by means of corresponding screws 23.

The top chains 12 are driven by two driving pinions 24 keyed on a shaft 25 receiving its rotational movement through a transmission 26 connected to the driving shaft 11 and ensuring synchronous movement of the four chains.

The bottom chains 5 and top chains 12 are thus installed in such a manner as to remain always parallel and always equidistant.

The chains are tensioned by means of two jacks 27 in respect of the bottom chains, and two jacks 26 in respect of the top chains. These jacks may be hydraulic or pneumatic. Supply pipes 29 make it possible to introduce the impregnating product, for example bitumen, into the tank. The bitumen outlets 30 are situated at the two ends of the tank 1.

Coils 31 are distributed over the bottom and walls of the tank in order to enable the bath to be heated by circulating hot oil (thermal fluid) or steam therein.

A reservoir 32 having a heating jacket enables the bitumen or other impregnating product coming from the slides 8 of the bottom chains to be recovered.

A reserve vessel and pumping unit enable the impregnating product to be recycled together with makeup product.

The slides situated outside the bath may be completely or partially heated in order to prevent the impregnating product from sticking to the chains, which would have the effect of considerably increasing the driving torque.

The conveyor chains are arranged so as to drive, in a continuous succession, sheets or boards of card or other similar material, whether corrugated or otherwise. For this purpose they are constructed as illustrated in FIGS. 2 to 4, which show part of the bottom conveyor system comprising to two chains The chains 5 are composed of rollers 33 running on the slides 6 and connected together by the links 34. The rollers 33 of the two chains are mounted on rods 35 carrying a tubular spacer 35' and thus connecting the rollers facing one another on the two chains, while ensuring the parallelism and constant spacing of the two chains.

Over the spacers 35 (-FIG. 3) there are clipped flat springs 36 forming a cradle and intended to serve as support for the sheet or board 37 to be impregnated. The ends of each spring are rolled to enable them to surround the spacer 35 and to fit by pressure over two consecutive spacers.

At the two ends of the spacers there are also fixed flat springs 38 (FIG. 4) the ends of which are shaped like those of the springs 36, but which are intended to hold the sheets or board laterally and to prevent them from coming into contact with the chains.

For the top chains 12 the springs 36 and 38 are similar to those illustrated in FIGS. 3 and 4, but they are placed on the spacers with their curved part at the top instead of being at the bottom.

The sheets or boards 37 can thus be held between the support springs of the bottom chains and the spring of the top chains, resting on the former and being capped by the latter, as shown in FIG. 5.

The operation of the installation will be understood from the following:

The sheets or boards 37 are placed in position between the chains at the entry E, on the right in FIG. 1. The two bottom chains 5 follow theinclined slide 7 and plunge to the bottom of the bath, circulating horizontally in the latter, and then rise on the inclined slides 8 and pass under the tank to return to the inlet.

The two upper chains 12 follow the inclined slides 14 at the same speed as the bottom chains 5, but at a distance from the latter which corresponds to the height of the sheets to be impregnated. They drop to the bottom of the bath and then rise, following the inclined slides 15 and pass above the tank along the slides 16.

During the travel of the four chains, the sheets 37 are transported in the bath while held vertical, and when they arrive at the outlet S they can easily be collected because the shape of the support springs permits their release at the moment when the chains arrive at the driving pinions 10 and 24 which move the bottom chains away from one another.

lt should be noted that the entry into the bath and the withdrawal of the sheets or boards 37 from the latter are effected progressively and that at the outlet end they have a sufficient path for draining purposes.

The tank is partly closed at the top by movable panels 39.

Hoods 40 and 41 are fitted over the open portions at the inlet and outlet.

The hood 40 at the inlet end can cover the opening and permit impregnation in a closed container, but a group of fans situated in the chimney 42 may be mounted on it.

The hood 41 at the outlet end is provided with a chimney 43 in which there is placed a fume extractor fan and a filter for purifying air discharge to the atmosphere.

An opening is provided in each hood for the entry and exit of the sheets, and the sheets or boards placed at regular intervals and moving with the chains complete the closure of the hoods.

Modifications of form and details may naturally be made to the installation described above simply by way of example without limitation, without thereby departing from the spirit of the invention.

What we claim is:

1. Apparatus for continuous impregnation of sheet material comprising a tank of parallelepipedic shape, the two end walls of which are inclined so as to permit progressive ingress and egress of material in sheets in a continuous succession into and out of a bath of liquid impregnation material introduced into said tank, two pairs of conveyor chains, a bottom pair and a top pair, holding said sheets vertically between them and carrying them from an inlet end between the chains to the outlet end where the sheets are disconnected after complete immersion over a major part of their travel in the bath.

2. Apparatus according to claim 1, wherein spacers connect the pair of upper chains and the pair of lower chains, said chains being parallel to one another, said spacers having clipped springs to hold the sheets in a vertical position and at regular intervals in the bath.

3. Apparatus according to claim 1, wherein the bath is provided with heating coils at the bottom and on the inner walls of the tank, for circulation of hot fluid.

4. Apparatus according to claim 1, wherein, a reservoir and a pumping unit are provided for recycling of the impregnating material simultaneously with makeup material.

5. Apparatus according to claim 1, wherein the chains move at a speed varying in dependence on the thickness of the sheet to be impregnated and the density of the impregnating materi- 6. Apparatus according to claim 1, wherein said chains run on slides which are heated outside the bath to prevent material from sticking to the chains. 

1. Apparatus for continuous impregnation of sheet material comprising a tank of parallelepipedic shape, the two end walls of which are inclined so as to permit progressive ingress and egress of material in sheets in a cOntinuous succession into and out of a bath of liquid impregnation material introduced into said tank, two pairs of conveyor chains, a bottom pair and a top pair, holding said sheets vertically between them and carrying them from an inlet end between the chains to the outlet end where the sheets are disconnected after complete immersion over a major part of their travel in the bath.
 2. Apparatus according to claim 1, wherein spacers connect the pair of upper chains and the pair of lower chains, said chains being parallel to one another, said spacers having clipped springs to hold the sheets in a vertical position and at regular intervals in the bath.
 3. Apparatus according to claim 1, wherein the bath is provided with heating coils at the bottom and on the inner walls of the tank, for circulation of hot fluid.
 4. Apparatus according to claim 1, wherein, a reservoir and a pumping unit are provided for recycling of the impregnating material simultaneously with makeup material.
 5. Apparatus according to claim 1, wherein the chains move at a speed varying in dependence on the thickness of the sheet to be impregnated and the density of the impregnating material.
 6. Apparatus according to claim 1, wherein said chains run on slides which are heated outside the bath to prevent material from sticking to the chains. 